Television apparatus



D L A w a TELEVI SION APPARATUS s Shee'ts-Sheet 1 Filed Aug. 3, 1940Aug. 111, 1942., G, D 2,292,979

TELEVISION APPARATUS Filed Aug. :5, 1940 s Sheets-Sheet 2 gm 52 K\ 354If l/az 60 l "'0 97 7 I v W Aug. 11, 1942. a. WALD 2,292,979

TELEVISION APPARATUS Filed Aug. 3, 1940 3 Sheets-Sheet 3 /l\/ Q/ENTO I?650265 WA L 0,

.Patented Aug. ll, i942 Uhli'iififi STATES FATENT @FFEQE 11 Claims.

The present invention relates generally to television apparatus, andmore particularly to television receivers and to elements comprising thesame.

In one form of the television receiving apparatus the cathode ray tubeemployed has an internal volume of over one cubic foot, which must bemaintained at a high vacuum and presents a danger of explosion. Thefluorescence employed as a screen must be applied on the glass verythin, for fluorescent material is opaque and the light generated by theelectronic beam striking the interior of the fluorescence must showthrough the fluorescent material, and so, even if a high voltage couldbe employed to produce a more brilliantly illuminated image, it couldnot be used as a practical matter, as the very thin fluorescent materialwould be damaged permanently thereby and the tube would become useless.A large size of the image means that the cathode ray electronic streamhas to cover a much larger area and the tube must be so much larger. Ina 24 screen, the tube contains several cubic feet of volume and willrequire 30,000 to 50,000 volts.

The danger involved with such voltages and large' vacuum containers usedin residences need not even be stated. Even a 12" x 12" image tuberequires voltages too high and vacuum containers too large for use inresidences.

An object of the present invention is to overcome the foregoing byutilizing the illuminosity produced in the inside of the cathode raylamp by the electronic stream or beam striking fluorescent materialappliedon a metal anode, such as, say, nickel. Such a metal anode isplaced near the top of the envelope of the conventionall known cathoderay television tube. This anode is preferably a concave disc and issecured so that it is slightly tilted to one side in respect to theelectronic beam. A second metal reflector of nickel, chromium-plated andhighly polished, may be located somewhat lower in the tube in line withthe metal anode reflector, so that any light produced in the inside ofthe tube by the fluorescent material concentrates into this lightreflector which, in turn, projects the light out- Wards from the tubethrough a suitable window. This latter light reflector may bemechanically and electrically secured to one of the cathode ray tubeelements, such as the first anode or deflecting plates for properdegassifying, and is of such a concaveness as to cause the light beam ator near the nodule point to be at the window of the envelope of thetube. The tube envelope may b metal except for a small sealed lens wherethe beam passes through, thus shielding the entire tube from outsideinterference.

Under these conditions, as the anode is being scanned by the electronicbeam, the image in the form of scanned light is reflected into the lowerlight reflector which, in turn, reflects the image outward through thelamp window to be developed ultimately on a screen for the televisionviewer. The size of the image may be larger and controlled by a lens, tofocus at will. The fluorescent material may be applied heavy and neednot be of a transparent material. It should, however, be rememberedthat, as the image is increased on the screen, the illuminosity isdecreased in the same proportion, since the light covers larger areas.Hence, the size of a conventional tube thus modified must still be largeto produce a large image.

However, with the optical television scanning system described in mycopending application for patent Serial No. 264,876, filed March 30,1939, the tube may be small, may use a comparative low voltage, and yetwill produce a largesize highly brilliant image. The cathode ray tube soemployed is always at nearly a constant current, but produces lightmodulation by changing the concentration of the electronic beam;

There may be used either the conventional cylindrical first anodewith-rectangular slots for the electronic beam to pass through it, or inits place two plates of the same potential may be used to compel theelectronic beam to form a fanshaped ribbon, so that the maximumcross-section of this ribbon electronic beam at the aforesaid secondmetal anode is, say, 2" x A", while the minimum cross-section is A" xA". The fluorescent material is applied to the concave side of the metalanode only in a diametric line of, say, slightly less than A" width.This anode is so positioned in relation to the elements of the tube asto form a cross between the line of fluorescent material and thecross-section of the electronic beam. Hence, only /4" x A" of thefluorescent material can-become illuminated at any instant, which is thecross-section where the electronic beam ribbon crosses the fluorescentline.

When there is no incoming television signal, the electronic beam isfan-shaped with a broadside of the two inches at the top and, therefore,only about one-eighth of the total electrons can impinge on thefluorescent material. Further, as the second anode is metal and moreelectrically conductive than the fluorescent material, actually only asmall fraction of the electronic beam is transformed into light. Thisrepresents the dark spot of the image.

Immediately above the first anode Plates of the tube is located a set ofmodulating plates p sitioned at right angles to the first anode lates orto the rectangular slot in the cylinder should the same be used. Bothmodulating plates are energized by the same potential. and areelectrically connected in series with an amplifler that receives thetelevision signals applied across its cathode and grid. The arrangement,therefore, applies the required television electric impulses to the setof modulating plates only when a television impulse is received. When astrong television signal is received, these modulating plates condensethe fan-shaped beam into a. narrow beam of, say, less than /4", and incombination with the first anode plates they cause the electronic beamto have a square crosssectional shape of less than A" x /4". so that allof the electronic beam impinges on the fluorescent material and producesa strong quantity of light. This is the bright point of the image; anyintermediate television signal received produces a correspondingcontraction of the fanshaped electronic beam and, in turn, acorresponding quantity of light is produced. Thus, the modulating anodeplates modulate the television light by varying the quantity ofelectrons applied to the fluorescent material and that applied to themetal plate, and thereby vary the light produced.

Above the modulating anode plates is positioned one set of theconventionally used deflecting plates which are disposed at right anglesto the modulating plates. These deflecting plates are energized by, say,the 60-cycle house current, or a harmonic thereof, saw-tooth style, tocorrespond to the transmitter, each plate being charged with oppositepotentials. thereby moving the constant quantity electronic beam to andfro along the fluorescent diametric line. The fan-shaped electronicribbon beam forms the ordinate in the tube (not image) and thefluorescent material the coordinate, and light is produced only wherethey cross one another, the quantity of light so produced depending onthe intensity of that quantity of the electrons of the electronic beamwhich are impinging on the fluorescent material. When the electronicbeam is fan-shaped, the minimum of illuminosity is produced; when thefan-shaped electronic beam is condensed into a bar shape, the maximum ofilluminosity is produced.

During one image frame, the electronic beam travels once along thediametric line of the fluorescent material and a line of light is formeddot by dot which corresponds in intensity to the incomingtelevision-signal at each instance, each clot overlapping the other, butat each instance it is corresponding in illuminosity to the televisionsignal received. Each light dot as it appears on the second anode isreflected into the lower reflector at about one-third the size and, inturn, reflected outside of the tube through the lens or window in thetube and on a single or approximately 5 /2".

scanning lens reflector, preferably prismo-con- I cave. This singleprismo-concave scanning lens causes the thin light beam to travel awidth of about, say, 5 /2" in the form of a thin light line or beam, ashereinafter explained.

The cathode ray tube with the reflector and the single prismo-concavescanning reflector form one unit" of the television system. The singlescanning reflector is so positioned as to cause the line scanned tocross the width of the reflector and is tilted either upwards ordownwards to cause the light beams, so scanned, to reflect each in turnupwards or downwards and into three scanning reflectors which form the"second unit" of the television system.

The scanning reflectors are positioned as though placed inside of a rimof a wheel. They are aligned one with the other and each one is slightlytilted longitudinally so that the light beam, as scanned, will reflectfrom one scanning reflector to the other. The elements of the secondunit of the system may be positioned at an angle of about 45 to thesingle scanning reflector of the first unit. That is, the relationshipls such that the horizontal light described and scanned on the singlescanning reflector describes a diagonal across the six multi-focal racesof the first scanning reflector. Hence, if the first scanning reflectoris 4" x 4", the light line scanned upon the first scanning reflectormust be the square root of 4 squared plus 4 squared, Thus, a diagonallight line beam is described on the first scanning reflector.

Each of the three scanning reflectors has six multi-focalprismo-concave, or any other multifocal, scanning faces. Therefore,one-sixth of the diagonal light line so scanned falls on the nextmulti-focal lens substantially instantly. As the light beam so scannedby each multi-i'ocal lens of the first reflector reflects into thesecond reflector, each multi-focal lens scans a full line on same acrossthe full width of the second scanning reflector. Hence, there are sixinclined light lines scanned across the second scanning reflector, eachline being inclined about $6" or about and each light line is describedon the second scanning reflector below the preceding one. As the secondscanning reflector also has six multi-focal scanning faces, each lightline as scanned across the second multi-focal scanning reflectorreflects and scans six lines across the third scanning reflector.Therefore, the one diagonal described and scanned across the firstscanning reflector describes and scans thirty-six lines across the thirdscanning reflector and each line is on an incline of twothirds dividedby six. or /6". As the third scanning reflector also has six multi-focalscanning faces, each line scanned and described on the third scanningreflector describes six lines on the screen. Thus, the single diagonaldescribed and scanned on the first scanning reflector now scans anddescribes 6X36. or 216 lines on a screen. If we have a 24" screen, eachline is inclined 6X36 divided by six, or $6", and each line is scannedand described below the preceding one.

The third unit of the television system is the expanding mirror and thescreen. Hence, the second television unit should be placed at such anangle to the third television unit as to produce straight horizontallines on the screen in a manner hereinafter described. It is notnecessary to physically place each television unit at difl'erent angles,as a mirror placed in combination with these units and at a certainangle to each unit will produce equivalent results, as hereinafterdescribed.

Assuming that a 60-cycle house current is superimposed on a directcurrent voltage and by well-known means is converted to a saw-toothscanning current and applied to the scanning plates, then inone-sixtieth of a second, the fanshaped (or moves slowly -of the secondanode and quickly returns to the starting point. During the return, notelevision signal is received, and, therefore, the electronic beam isfan-shaped, and there is but a very dim light on the screen. Thus,nearly one-sixtieth of a second is consumed by the slow one-way movementof the electronic beam across the diametric line of fluorescentmaterial. In thirty double interlaced frames per second there are sixtyhalf image interlaced frames per second, which is equivalent to thescanning thus produced, and, since each half frame has 216 lines scannedon the screen, the whole image frame has 432 lines per second. The ninelines less than the conventional standard 441 line image can be absorbedin the return of the electronic beam or in the descent of the saw-toothscanning current. By changing the number of bifocal faces in each of thethree multi-focal scanning reflectors, any number of lines per image canbe produced, thus multi-focal scanning lenses with sevenconcave-prismatic lenses would produce 7 x '7 x '7, or 343 lines perhalf frame and 686 lines per image frame, and eight bifocal faces wouldgive 8 x 8 x 8, or 512 lines per half frame and 1024 lines per imageframe.

The television receiver may be synchronized by the means shown in Figs.17 and 17a. and described in the specification of my copendingapplication Serial No. 264,876, filed March 30, 1939, to any present-dayconventional television transmitter.

More specifically, another object of the present invention is to providea novel television receiver which is adapted to obviate the deficienciesof receivers now known and in use.

Another object is to provide a novel television receiver which isadapted to produce a large-size clear image.

Another object is to provide a novel television receiver which isadapted to produce a large-size clear image at relatively low voltage.

Another object is to provide a novel cathode ray tube for use as anelement of a television receiver which is small in size, yet which willproduce a large-size clear image at comparatively low voltage.

Another object is to provide a novel television receiver tube which isadapted to modulate the brightness of the moving image spotsubstantially instantaneously.

Another object is to provide a novel television tube which is entirelyscreened from outside magnetic or static interferences.

Another object is to provide a scanning system and a method of effectingthe same which eliminates ordinate and coordinate scanning.

Another object is to provide a novel combined television tube and primemover to render the optical television receiver entirely automatic inaction, thus eliminating any mechanical or physical prime mover.

Another object is to provide novel scanning reflectors that scanconcentrated light beams, and to provide a system of disposition of sameto produce an ultimate clear image.

Another object is to provide a novel diagonal scanning system to scanthe image to eliminate the ordinate and coordinate scanning signals, anda method of performing the same.

Another object is to provide a novel cathode ray tube which includes ametal anode against which the electronic stream plays to utilize thecomplete illuminosity thereof.

Another object is to provide. a novel, inexpensive, simple televisionreceiver which produces a large clear image.

Another object is to provide a novel television receiver tube which issmall and which functions with a relatively low voltage.

Other objects and advantages will be apparent from the followingdescription, taken in conjunction with the accompanying drawings, inwhich:

Fig. 1 is a diagrammatic view of a portion (the first unit) of thepresent novel television receiver, particularly showing the tube;

Fig. 2 is a diagrammatic view of a metal television receiver tubeconstructed in accordance with the teachings of the present invention;

Fig. 3 is a plan view of the novel metal anode employed in the tubeshown in Figs. 1 and 2, disclosing the fluorescent strip;

Fig. 4 is a diagrammatic developed view of the glefining shapes of theelectronic beam of the Fig. 5 is a perspective view of one type of anodehereinafter referred to as the first anode;

Fig. 6 is a view of another type of anode em ployed in the manner of theanode shown in Fig. 5;

Fig. '2 shows diagrammatically a concave reflector with light beamspassing through the principal focus thereof;

Fig. 8 illustrates diagrammatically a single prism and a reflector withlight beams reflected from the latter and passing through the former;

Fig. 9 illustrates diagrammatically a double prism and a reflector withlight beams reflected by the latter and passing through the former;

Fig. 10 is a cross-section of a prismo-concave scanning lens reflectorwith light beams passing therethrough;

Fig. 11 is a cross-section of a multi-focal scanning lens reflectorwhich is concave at the back and which includes six concavities in thefront side;

Fig. 12 is a cross-section of a prismo-concave scanning lens reflector;

Fig. 13 is a cross-section of a concavo-convex multi-focal scanning lensreflector;

Fig. 14 is a cross-section of a prismo-convex scanning lens reflector ofmulti-convex configuration;

Fig. 15 is a cross-section of a prismo-convex scanning lens in a metalreflector holder;

Fig. 16 is a side view of a lens and holder together with fasteningmeans for securing it in a receiver cabinet;

Fig. 17 illustrates diagrammatically the disposition of the lensreflectors which receive the optical image emitted from the cathode raytube and develop it on a screen;

Fig. 18 is a front view of the scanning lens refiectors and screen shownin Fig. 17, diagrammatically illustrating the multiplication of a singlediagonal scanning light beam, and the developing therefrom of thedesired number of image lines on the screen; and,

Fig. 19 illustrates diagrammatically how light lines may be made toultimately appear at any angle of inclination desired. 1

Referring to the drawings more particularly by reference numerals, inorder that the theory and operation of the apparatus may be under-.stood, there is disclosed in Fig. 1 the first unit of an opticaltelevision receiver constructed in ac,- cordance with the teachings ofthe present in vention, There is an antenna 2| which, is adapted toreceive a television radio signal, and a con--v ventional commercialtype television receiver 22 which precepts, detects and amplifies thesignal.

'An'amplifying circuit 29 is connected to the receiver 22 and includesagrid and-cathode 24 I 7 across which the television signal is applied;The I j amplifying circuit 23 is: connected to both plates of amodulatinganode 25 forming part of a television tube 26 and to a cathode21 of the tube V 26, so that the television signalsv or impulses arepplied to both. o I

A focusing anode 28 is-disposed: below the modulating anode 25. Thefocusing anode 28 comprises a pair of parallel plates 29'connected v byan end piece 38 having erect-angular opening 3|, therein (Fig. Therectangular opening I 7 :permits electrons from the cathode'2'l 'to passtherethrough and the plates 29 concentrate the bcam'so formed in thosetwo directions only,

by :broken lines in the same flg'ure.- In other words, at the strongestsignal, the electronic beam 41 is bar-shaped to concentrate all of theelectrons on a corresponding cross-section of the fluorescent strip 49,whereas, with no signal being received; the electronic beam 4! is fanShaped reduce to a minimum the electr ns A impinging on the fluorescentstrip 49.

' I A conventional Gil-cycle saw-tooth'current de- I while permittinglitto spread in the directions at right anglesthereto. A conventionalcylindrical 33 in the ends 34 thereof may be employed if preferred (Fig.6)

The modulating plates of the I modulating tiaiappliedto the focusinganode 28. Between the focusing anod28an'dthe cathode 21, which I H is aheavy duty unit heldunder red heat andi I I :capable ofsupplyingavlargequantity of elec- Qtrons'. isa cup-shaped grid 31 having a hole, 98

therethrough.

Direct current power supply terminals 48 and 4| supply rectified D. C.electric power from a I I focusing anode 82 having rectangular openingsveloper 551s connected tooan ordinary SO-cycle house current by leads SIand 52 (Fig. l); The developer-'50 includes a device similar to thatshown in Figs. 17 and 17a and described in the specification of mycopending applicatlonseriali No; 264,876, filed March 30, 1939; so thatthe present device can easily be brought in phase] relation with thescanner of a transmitter; As

shown in Fig. 1,: the Gil-cycle saw-tooth current is p rposed on the no.current and'applied to a pair of'plates 54 which'comprise a deflecting ii anode 55; As is well-recognized in the art, this arrangement causes:the electronic beam 41' to move slowly in one direction, as in thedirection i i I of the arrow 56 (Figs. land 3) and quickly in arrow 51;The fluorescent strip 49 (Fig. 3) need not be,

power pact (not shown) acrossa resistance 42, 7 i

The aforesaid grid 31 is held in a negative potential to the cathode 21at any preferred degree through a movable contact point 44 movablyconnected to the resistance 42. A suitable lead 45 connects the grid 31and the contact point 44. Through manipulation of the contact point 44,the quantity of electrons in the electronic beam 41 produced by thecathode 21 may be increased or decreased, as desired. At a selectedsetting of the contact point 44, a constant electronic current or beam41 flows between the hot cathode 21 and an anode 48 located at the farend of the tube 26.

The anode 48 comprises a metal plate of dished or concave circularconfiguration (Figs. 1 and 3). Running diametrically across the anode 48is a strip 49 of fluorescent material which is preferably of a width ofslightly less than The aforesaid constant quantity of electronic current41 flowing between the heavy duty cathode 21 and the anode 48 is notmodulated or changed by the television signals, but continues constantat the rate determined by the setting of the contact point 44. However,the amount of it that is caused to impinge or strike the fluorescentstrip 49 is modulated or changed by the television impulses as suppliedby the plate of the amplifying circuit 23 to the modulating plates 25'.The shape of the electronic beam 41 when no television signal is beingreceived is shown in solid lines in Fig. 4, whereas the shape when thetelevision signal is strongest is shown 'to the appreciable width ofabout ,4". I clear from Fig, 3, only those electrons'of they I the otherdirection, as in the direction or the of transparent material, inasmuchas the anode 48 is of metal. The material is applied heavily As, is

eelctronic beam '41 within the square designated 8 I 60, produce light,inasmuch; as the remainder thereof :fallson the metallic anode 48(Hence, I as stated, when the strongest signal is received, s all ofitheelectrons of the beam 41 are concentrated within the square somewherealong the I fluorescent strip 49. As the signal weakens, the q I beam 41becomes fan-shaped in proportion to the intensity thereof, so that-onlya proportionate I number of electrons strike theifluorescent strip49twithin the square 60.

r The deflectingplates 54 move the beam'4'l in the directionof the arrow58" from the end SI of the strip 49 to the end 62 in slightly less thanone-slxtieth of a second. The brightness of the light square advancesand recedes in strength from point to point and from instant to instantas modulated by the television signal received by the modulating plates25'. It is well-known that fluorescence is always accompanied byphosphorescence; that is, fluorescent material when lighted by electronsstriking it remains lighted for a short instant thereafter due tophosphorescence. In effect, a lag in the lighted dots of the image isproduced and a smeared picture results. The metal anode 48 eliminatesphosphorescence as a practical matter, for the fluorescent light diessubstantially after the electrons stop striking it. The demarkationbetween strong and weak light points is very sharp and deflned with thepresent device so that the tube or lamp is sensitive to any number ofmegacycles and can produce a clear image of any number of lines.

Within the tube 28 suitably located in respect to the anode 48 is areflector 84 which receives light flux 85 from the anode 48. In turn, alight beam 88 is reflected from the reflector 84 through a window 61 inthe metal envelope 26' of the tube 26. The beam 66 passes through aconcentrating lens 88 to strike a further concentrating concavereflector 69, whence it passes to a single scanning reflector unit 18.The reflector 64 is metal and is mechanically secured to any element ofthe tube and is electrically connected to the reflecting plates 54. Thereflector 64 takes no part in the electric circuit reaction of theelements of the tube 26, but is electrically connected to the deflectingplates 54 or some other element for the purpose of enabling the tube 26to be completely degasifled.

As stated, the light beam 66 is concentrated by the lens 68 so that theincident light beam swings lengthwise on the surface of the onedimensional concave reflector 69 a very short distance, as (a singlelight beam is considered herein for purposes of illustration as a matterof clarity) Since the original length of the generated light line causedby the electronic beam 41 moving between the points 6| and 82 (Fig. 3)is 2" and the length of the line at the reflector 69 is but A",manifestly the dot light beam has been concentrated to one-sixteenth itsoriginal size and is manifestly sixteen times as bright. As thecross-sectional area of the light line at any instant was less than A"squared, the light dot on the reflector B9 is less than A" x or lessthan ,4,4" in crosssectional area. In the perpendicular direction of thelight beam 69, the instantaneous dot light beam is still furtherconcentrated by the concavity of the reflector 69. As the incident lightbeam 66 swings from a to b (Fig. 1), it forms a certain incident anglewith the normal to the straight dimensional side of the reflector 69 andproduces a light beam 66' at a reflected angle of twice the deflection.The angle effected by the beams 66 and 66 is very large and varies asthe beam 66 swings from a to b, thus making the corresponding swing of Ato B of 66' of suflicient width to cover the entire width of theprismatic part of the prismo-concave lens reflector ID. The lensreflector "m is silvered on the convex side to reflect and deflect theconcentrated light beam ll (Fig. 17) through a wide angle to scan a lineof, say, 5 in length, whereby it scans the whole width of a firstscanning reflector along a diagonal line H3 (Fig. 18).

Before proceeding to a descriptional analysis of the second unit of thepresent receiver, it is well to consider specific lens reflectorelements and combinations which can be employed.

Referring to Fig. '7, there is showndiagrammatically a concave reflector80. Any light beam at reflected by the reflector 80 will pass throughthe principal focus 82 thereof. All of such light beams 81 will beconcentrated at the principal focal point 82.

In Fig. 9, there is shown a double prism 8t disposed between the concavereflector 80 and its principal focus 82, the double prism 84 beingrelatively close to the concave reflector 80. Each beam or line of light8| will be deflected by the double prism 86, each light line beingdeflected to a different degree away from the principal focus point 82except the center one, which, of course, will continue to pass throughthe central focus point 82. By selecting the respective dioptralstrengths of the reflector 80 and of the prism 84, so that the former isslightly more contracting than the latter is diverging, for example,selecting the concavity of the reflector 80 as four diopters and theprism 84 as but about a resultant of slightly less than four diopters,the very narrow beams 8! will still follow the directions compelled bythe action of the double prism 84, yet will remain on the wholeconcentrated. The foregoing is true, due to having the reflector tilmore concentrating of the light beam than the prism 84 is divergent ofit. At specific distances from the reflector 80, a series of principalfocal points will be formed and each very thin light beam 8| will haveits principal focus at a different location. When a thin light beam ismoved across the reflector (Fig. 9) it will reflect and be refracted bythe prism 84 so that the principal focal point will move rapidly from8241 to 82c in the direction of the arrow 85, yet the beam 8| willconcentrate and become thinner as it is refracted towards 82a. Thedirection and concentration of the beam- 8| are resultants of directionsand concentrations of the light beams 81 reflected from the reflector 80and refracted by the double prism 84.

- In Fig. 10, there is shown a single scanning lens reflector 86 whichcombines the reflector 80 and the prism 84. In a thick mirror lens, suchas a A lens reflector, the outer glass becomes a lens superposed upon amirror and, since the light beam has to pass the glass of the reflectortwice (into and out of the reflector), only onehalf of the double prism84 is required to accomplish the same result. The scanning reflector illis of the type exemplified by the lens reflector 86. The light line amcomprises two broader lines which come closer and closer together untilthe focus point 82a is reached. The slightest movement of the incidentlight beam to one side as it strikes the reflector portion of the lensreflector 86 moves the nodule point 82a a greater distance in thedirection of the arrow 33a.

In Fig. 11, there is shown a lens reflector 88 of the type disclosed inmy aforesaid copending application, in which, in a preferred embodiment,the mirrored reflector side 89 has a curvature of flve diopters, thegeneral curvature of the exterior side at of the lens is of but slightlyless than one and one-half diopters, and the individual lens curvatures91 are of slightly more than two diopters. The scanning lens reflectors88, when employed as a part of the present receiver, are preferably setat about 15 from each other for proper scanning, assuming the size ofeach as 4." x .4". The effective light beams are thin and diverging andscan swiftly across the succeeding reflector.

There is shown in Fig. 8 the effect of a single prism 93 on light beams8i reflected from the reflector 80. The reflection of the light beams 8!is more towards the thicker part of the prism 53. The principle of thesingle prism 93 and the reflector B8 is employed in the formation of ascanning lens reflector 95 (Fig. 12) to avoid an undesirablecharacteristic of the lens reflector 88 which requires that theindividual lens curvatures 9! be narrower from the center towards theend in order that each covers exactly the same line area of thesucceeding scanning lens reflector. In the lens reflector 85, there aretwo central lenses 95 comprising a double prismatic lens, each with thethicker side of the prism towards the center. At each side of the lens96 are single prisms S'l'to deflect the light more towards the centerand the inclination of each prism is such as to cover exactly the sameline area as the succeeding scanning lens reflector. The thicker ends ofthe prisms 91 are disposed towards the center of the scanning lensreflector as. The correct inclination of each prism 96 and 97 furthercorrects any slight existing error, so that each scanned line is placedon the exact same width of the succeeding scanning lens reflector as theline scanned by the adjacent bifocal face or prism.

In Fig. 13, there is shown a scanning lens reflector 99 having doublemulti-focal lenses I and II. In this construction, the resultant diopterof the lenses I 0| must be less than that of the lenses I00 to produce aconcentrated and diverging scanning beam. The lenses I00 are mirroredand concentrate the beams, whereas the multi-focal lenses IOI refractthem in a diverging relationship.

In Fig. 14, there is disclosed a convex pris-' matic lens reflector I03,which includes a reflector portion I04 made up of a plurality of concavereflector segments I05 and prisms I06 and I01. Preferably, the curvatureof the reflector segments I05 is about four diopters, while the radiusof the lens I03 is about '15".

In Fig. 15, there is shown a lens I09 in association with a holder III]which together comprise a scanning lens reflector I I I. The holder H0is preferably of chromium-plated metal highly polished on the concaveside to reflect light. The lens I09 is of plastic material, such aslucite." This construction permits the use of plastic material forlenses which molds easily to the desired shape to produce lenses toperform all their intended functions. The disclosed holder II 0 has twometal end pieces II2 (Fig. 16) by means of which the scanning lensreflector III may be mounted in a suitable cabinet, or the like.

Referring again to Figs. 1 and 17, it has been shown that the light beam66 swings and scans the single scanning lens reflector 10 from A to Bacross the width of the double prism thereof. For the purpose of thepresent analysis, the first unit of the present receiver, whichcomprises the tube 26 with all of its elements, the lens 68, the mirror69, and the single scanning reflector 10, is positioned at 45 from theorbital circle of three scanning lens reflectors 15, 16 and 11 (Fig.17). Hence, the light beams reflected from the reflector 10 is adiagonal line I I3 as thrown on the scanning reflector (Fig. 18). Thelight beam 1I scans at 45 to the plane of the drawing sheet, while thescanning reflector 15 is positioned vertically with respect thereto withthe multi-focal lens faces inside directed to receive the light beam H,the multi-focal lenses extending from the top II5 to the bottom II5 ofthe scanning reflector 15. In Fig. 17, one-half of the outside of thescanning reflector 15 is observable. The scanning reflector 15 is placedin a position above the reflector 10, so that a reflected light beam H1is reflected upwardly, as shown. As stated, the scanning reflectors 15,16 and 11 are in alignment with each other and are positioned as thoughlocated on the inner side of the rim of a wheel. Hence, the light beam II1 scans normal to the plane of the drawing within the width of thescanning reflector 16, the multi-focal lenses of which extend from II8to II 9. From the light beam II1 scanning the reflector 16 there isreflected the light beam I20 which strikes the scanning reflector 11,the multi-focai lenses of which extend from I 2| to I22, from whichthere is produced a reflected light beam I23. As aforesaid, the lightbeams II1, I20 and I23 scan in directions normal to the plane of thedrawing through a width of 4", which is the afore-assumed width of thescanning reflectors 15. 16 and 11, which is efiected substantially asthe light beam 1| moves from II5 to H6, describing the diagonal lightline II3 across the reflector 15 (Fig. 18). As the vertical angledefined by the light beams H and H1 changes, so the corresponding anglesdefined by the light beams H1 and I20, I20 and I23, and I23 and I24change accordingly. Thus, each aforesaid light beam moves both acrossthe width of the respective scanning lens reflector 15, 16 and 11 and ascreen I25 as many times as refracted by the bifocal lenses, and onceacross the height of the same for each image half-frame. The light beamsII1, I20, I23 and I24 scan each one faster than the other at a directionnormal to the plane of the drawing in a manner described in my aforesaidcopending application for patent.

Close to the scanning reflector 15 is a longitudinal concentrating lensI26. There is a sim ilar concentrating lens I21 adjacent the scanningreflector 16, a concentrating lens I28 adjacent the scanning reflector11, and a concentrating lens I29 adjacent a reflector I30. The thinlight beam 1I scans swiftly the multi-focal lenses of the scanningreflector 15 in the direction 331: '(Fig. 10) and normal to the plane ofthe drawing (Fig. 17). The lens I26 further concentrates each light dotof the monochromatic light beam 1I so that they appear in scanningrelation to the scanning reflector 15 as but fine thin specks of verybright light. The concentrating lenses I21, I28 and I29 produce the sameeffect on their respective scanning reflectors and reflector. Since thereflected light beam II1 clears the lens I26, it scans the entire widthof the scanning reflector 16 normal to the plane of the drawing.Similarly, the reflected beams I20, I 23 and I24 clear the respectiveconcentrating lenses I21, I28 and I29, respectively, and each scans thesucceeding reflector normal to the plane of the drawing through thewidth thereof, each beam scanning faster than the preceding one.

Referring to Figs. 17 and 18, the light beam H, in scanning once acrossthe scanning lens 15, covers the distance a-g in describing theaforesaid diagonal light line I I3 (Fig. 18A). As the light beam 1Imoves from a to b (one-sixth of the scanning movement), the reflectedlight beam I I1 scans once completely across the face of the scanningreflector 16 to describe a complete light line I 35 (Fig. 183)Similarly, as the beam 1| moves from b to c, c to d, d to e, e to ,f,and f to g, each time the light beam II1 scans completely across theface of the scanning reflector 16 to describe, respectively, the wholelight lines I36, I31, I38, I39 and I40. In other words, each lens of themulti-focal scanning lens reflector 15 causes the incident light beam 1Ireflected as light beam II1 to describe a full light line on thesucceeding scanning reflector 16 and, therefore, the six light linesI35I40 are described on the scanning reflector 16, each of which has aninclination of but one-sixth that of the diagonal light line II 3, theangle comprising the vertical component or the respective light linediagonal segment a-b, b-c, etc.

By the same principle that the six light lines I35-l40 are developed onthe scanning reflector 16 from the single diagonal light line H3 on thescanning reflector 15, so thirty-six light lines are developed on thescanning reflector 11, and two hundred sixteen light lines are developedultimately on the screen I25 (Figs. 18C and 18D).

In other words, each of the light lines I 35-440 develops six lightlines on the scanning reflector II. The six light lines developed by thelight line I35 fall on the scanning reflector 11 within the verticaldistance from H on Fig. 183. The light beam I20, which typifies all ofthe light beams I35-I40. scans completely across the scanning reflectorI1, along the full light line I4I as that portion of it designated thelight line I35 (Fig. 18B) moves from a to b. Similarly, the light linesI42. I43, etc., are generated as the light line I35 moves from b to c, cto d, etc., respectively. In the same manner, the second full six lightlines are generated on the scanning reflectorl'l'l by that segment ofthe light beam I20 designated the light line I36, the third six lightlines by the segment designated I31. the fourth six light lines by thesegment designated I38, the fifth six light lines by the segmentdesignated I39, and the sixth six light lines by the segment designatedI40. The inclination of each of the light lines I, I42, I43, etc., isone-sixth of that of the light lines I35--I40, or one thirty-sixth ofthat of the light line II3. As aforesaid, two hundred sixteen lightlines I45 are developed on the screen I25, which form the components ofthe light beam I23, which is reflected by the reflector I30 as lightbeam I24. Each of the light lines MI, I42, I43, etc., which comprise thelight beam I23, I24 develop in rapid succession six full light lines I45on the screen I25. The inclination of each of the light lines I45 isone-sixth that of the light lines I4I, I42, I43, etc., or onetwohundred-sixteenth that of the original diagonal light line H3. Itbecomes necessary, therefore, only to provide for a small adjustment ofthe flat expanding mirror reflector I30 to bring the light lines I45 onthe screen I25 into straight horizontal positions.

The flat mirror reflector I30 is used to spread the light lines to forman image on a large screen of, for example, 24" x 24". Since, ininterlaced scanning, a line of light is placed on the screen alternatelywith a line of darkness, the scanned lines occupy in surface coverageonly a total of one-half of the height of the screen, or 12". In eachhalf image (interlaced) two hundred sixteen light lines are developed sothat the width of a light line as scanned on the screen I25 is /1s (12"divided by 216). The original dot of light produced by the fluorescentstrip 49 has a width of /4", hence the ultimate corresponding dotdeveloped on the screen I25 is condensed 4 /2 squared, or 20.5 times, sothat the aforesaid ultimate dot is 20.5 times as bright as thatoriginally produced in the fluorescent square 60 (the ratio is A"squared to his squared, or 4 /2 squared equals 20.5 times as muchlight). Therefore, a clear very bright image results on a 24" x 24"screen. The width of the light dots on the screen I25 need not beconsidered, for, as light travels 186,000 miles per second and there are60 x 216 x 432, or 5,598,720 light dots developed on the screen persecond, there is .04 mile (186,000 divided by 5,598,720) of light fluxfalling on each light dot of the image upon the screen I25. The scanninglens reflectors I5, 16 and TI may also be slightly concave in a verticaldirection to concentrate the scanning beams in a vertical directionalso, that is, in the direction at right angles to the scanningdirection of the beams II, In, I20 and I23.

Referring to Fig. 19, there is shown a method by which the dispositionof the first unit at a 45 horizontal angle from the second unit may beavoided. A flat reflector I50 is interposed between the single scanningreflector I0- and the scanning reflector 15, the reflector I50 beingpositioned either on a higher or lower level and at a horizontal angleof 60 from the single scanning lens reflector I0 while, at the sametime, it is inclined to the horizontal less than 45. The result is theappearance of the light beam II on the scanning reflector 15 as thediagonal light line H3. As shown in Fig. 19, the single scanningreflector I0 is positioned upright or vertically, with the bottom edge1.0 in a horizontal plane. The light beam 66', therefore, in scanningacross the reflector I0, describes the horizontal light line I5I, whichis deflected into and across the flat reflector I50. An inclined lightbeam I52 is, therefore, developed on the light reflector I50, inasmuchas the flat reflector I50 is positioned lower or higher than the singlescanning reflector 10 with the side edge I50 at the bottom displaced 60horizontally from the single scanning reflector I0, and inclined towardsthe latter about 45. It is to be noted that the face of the singlescanning reflector I0 is not observable. The scanning reflector I5 likethe single scanning reflector I0 is positioned vertically and at ahorizontal angle of approximately 60 from the single scanning reflectorI0. Hence, the reflected light beam II, as scanned by the singlescanning reflector 70, describes the required diagonal light line I I3on the scanning reflector I5, even though both reflectors I0 and I5 arepositioned vertically. By tilting the single scanning reflector I0slightly away from the reflector I50, the degree of inclination of thelatter to the horizontal can be reduced. Further, by using the cornerpoint I53 of the reflector I50 as a pivot and changing the inclinationor the horizontal angle of the same, any inclination of the light beam II3 from vertical to horizontal may be obtained. The reflector I30 (Fig.17) is so tilted to produce straight lines on the screen I25.

The afore-described and illustrated television receiver can readily beemployed as a transmitter by substituting photoelectric material for thefluorescent material of the fluorescent strip 49.

It is apparent from the foregoing description and analysis, taken inconjunction with the accompanying drawings, that the present inventionis adapted to and does fulfill all of the objects and advantages soughttherefor. Modifications of the disclosed and described embodiment of thepresent invention falling within the boundaries of the claims whichfollow are contem-- plated as fully within the spirit and scope hereof.

It is to be understood that the foregoing description and accompanyingdrawings have been given by way of illustration and example, and not forpurposes of limitation..the invention being limited only by the claimswhich follow.

What is claimed is:

1. In the art described, the method consisting of producing anelectronic beam, projecting the electronic beam upon a surface partiallycovered by fluorescent material, receiving television signal impulses,contracting and expanding the said beam under the influence of the saidimpulses. moving this electronic beam along a fluorescent materialtrack, thereby producing a linear motion of a television modulated lightbeam, intercepting this linear light beam motion by a plurality ofstationary multi-focal multi-lens reflectors disposed in a predeterminedrelationship to one another, thereby producing concentrated multiplereflections and refractions of the light beam, intercepting thesemultiple reflections of the light beam by a screen and reproducing animage corresponding to the television signals received.

2. In the art described, apparatus comprising a surface partiallycovered with fluorescent material, means to produce an electronic beam,means to project the electronic beam upon the said surface, means toreceive television signal impulses, means to contract and expand theelectronic beam under the influence of the said signal impulses, meansto move the electronic beam along a fluorescent material track toproduce a moving television modulated light beam, means to reflect andrefract the said light beam com- ;prising a plurality of stationarymulti-focal lenses to produce a plurality of movements of light beams,and means to reflect these light beams upon a screen to reproduce animage corresponding to the television signals received.

3. In the art described, the method consisting of producing anelectronic beam, projecting the electronic beam upon a surface embodyinga track covered by fluorescent material, receiving television signalimpulses, contracting and expanding the said beam in one direction underthe influence of the said impulses, moving this electronic beam at rightangles along the said fluorescent material track under the influence ofa periodic deflecting force, thereby producing a linear motion of atelevision modulated light beam, intercepting this linear light beammotion by a plurality of stationary multi-focal multilens reflectorsdisposed in a predetermined relationship to one another, therebyproducing concentrated multiple reflections and refractions of the lightbeam, intercepting these multiple reflections of the light beam by ascreen and reproducing an image corresponding to the television signalsreceived.

4. In the art described, apparatus comprising a surface embodying atrack covered with fluorescent material, means to produce an electronicbeam, means to project-the electronic beam upon the said surface, meansto receive television signal impulses, means to contract and expand theelectronic beam in one direction under the influence of the said signalimpulses, meansto move the electronic beam at right angles thereto alongthe said fluorescent material track under the influence of a periodicdeflecting force to produce a linear moving television modulated lightbeam, means to reflect and refract the said light beam said disposedmulti-focal multi-lens reflector as horizontal line areas of an image. I

6. In accordance with claim 1, a method of diagonal scanning comprisingdeveloping without mechanical motion a single diagonal light line inaccordance with the television impulses received from the scanning ofone-half of an image frame, and substantially instantaneously developingfrom said single diagonal light line without mechanical motion apredetermined plurality of substantially horizontal light lines on ascreen to form an image frame.

'7. In accordance with claim 5, in combination,

. a mechanically shielded television tube including tronic beam underthe influence of the said sigcomprising a plurality of stationarymulti-focal prismo-concave multi-lens reflectors disposed in apredetermined relationship to one another to produce a plurality ofmovements of concentrated ,light beams, and means to reflect these lightbeams upon a screen to reproduce an image corresponding to thetelevision signals received.

5. A television scanning construction comprising a plurality ofstationary multi-focal scanning reflectors disposed in. a predeterminedrelationship to one another, each reflector comprising a plurality ofprismo-convex lenses, a moving television modulated light lineintercepted by the multi-lenses of the first reflector is successivelydeveloped upon the other multi-focal multi-lens reflectors in increasingnumbers, depending upon the number of lens elements of each reflectorand the number of reflectors, means to direct the scanning light linediagonally across the first multi-focal multi-lens reflector, and meansto receive the light lines from the last of the aforenal impulses, meansto move the electronic beam along a fluorescent material track toproduce a moving television modulated light beam, means to reflect andrefract the said light beam comprising a plurality of stationaryscanning reflectors each comprising a concave reflector and a doubleprism disposed in adjacent relationship, and means to reflect theselight beams upon a screen to reproduce an image corresponding to thetelevision signals received.

9. In the art described, apparatus comprising a surface partiallycovered with fluorescent material, means to produce an electronic beam,means to project the electronic beam upon the said surface, means toreceive television signal impulses, means to contract and expand theelectronic beam under the influence of the said signal impulses, meansto move the electronic beam along a fluorescent material track toproduce a moving television modulated light beam, means to reflect andrefract the said light beam comprising a plurality of stationaryscanning reflectors each comprising a concave reflector and a prismdisposed in adjacent relationship, and means to reflect these lightbeams upon a screen to reproduce an image corresponding to thetelevision signals received.

10. In the art described, apparatus comprising a surface embodying atrack covered with fluorescent material, means to produce an electronicbeam, means to project the electronic beam upon the said surface, meansto receive television signal impulses, means to contract and expand theelectronic beam in one direction under the influence of the said signalimpulses, means to move the electronic beam at right angles theretoalong the said fluorescent material track under the influence of aperiodic deflecting force to produce a linear moving televisionmodulated light beam, means to reflect and refract the said light beamcomprising a plurality of stationary integral scanning reflectors eachreflector comprising a plurality of multiconcave multi-prism lenses,each of the prism lenses being disposed with the thicker porof thescanning reflector, and means to reflect these light beams upon a screento reproduce an image corresponding to the television signals received.

11. In the art described, apparatus comprising a surface embodying atrack covered with fluorescent material, means to produce an electronicbeam, means to project the electronic beam upon the said surface, meansto receive television signal impulses, means to contract and expand theelectronic beam in one direction under the lnfiuenoe of the said signalimpulses, means to move the electronic beam at right angles theretoalong the said fluorescent material track under the influence of aperiodic deflecting force to produce a linear moving televisionmodulated light beam, means to reflect and retract the said light beamcomprising a plurality of stationary scanning refiectors disposed in apredetermined relationship to one another each comprising a polishedconcave reflector and a plurality of integral concave prism lensesdisposed in contiguous relationship, and means to reflect these lightbeams upon a screen to reproduce an image corresponding to thetelevision signals received.

GEORGE WALD.

